Syntax: IGNORE ADD mask
        IGNORE TIME expiry mask
        IGNORE DEL [mask|num]
        IGNORE LIST [mask]

IGNORE is a useful tool to prevent abusive users
from using services. When an ignore mask is set,
any user matches the mask will be ignored by services.

IGNORE ADD adds the given user@host mask to the IGNORE list.
IGNORE DEL removes the given mask from the IGNORE list if it
is present.  IGNORE LIST shows all current IGNOREs; if the
optional mask is given, the list is limited to those
IGNOREs matching the mask.

Optionally, an expiry time can be given with the TIME
command.  The expiry time precedes the user@host mask, and
is specified as an integer followed by one of d (days),
h (hours), or m (minutes).  Combinations (such as 1h30m)
are not permitted.  If a unit specifier is not included,
the default is days (so +30 by itself means 30 days).  To
add an IGNORE which does not expire, use +0.  If the
usermask to be added starts with a +, an expiry time must
be given, even if it is the same as the default.  The
current IGNORE default expiry time can be found with the
SETTINGS command.
